It is well known in the art that it is a desirable feature of a liquid hard surface cleaner that it should have a certain viscosity. Indeed, viscosity allows a controlled handling, more specifically dispensing, of the product during use, as compared to a thinner product. Also, viscosity allows a better action of the product on non-horizontal surfaces, such as toilets, bath tubs and the like. That is because viscosity prevents the product from running down said surfaces, like thinner liquids would. Preferably, viscosity will be built up by a so-called self-thickening system as opposed to using a thickener compound for that specific purpose. Indeed, thickeners, such as gums or polymers have at least one drawback that they affect the formula cost, while providing only one benefit, which is thickening. They do not participate to the actual cleaning of the surface and therefore represent "inert" materials. Also, some thickeners are detrimental to the physical stability of the products they are formulated in. It is known in the art to formulate self thickened compositions where the thickening is achieved without the use of polymeric thickeners, see for instance EP 518 401 and EP 21 581.
But there are some drawbacks associated with viscosity. And a main drawback is that viscous products are typically difficult to rinse away, specifically because viscous products have a good cling onto surfaces and current self thickening systems lead to the formation of stable foams. Thus viscosity and ease of rinsing are somewhat conflicting requirements, but both are desirable in a single product for cleaning hard surfaces. It is thus an object of the present invention to provide a hard surface cleaning composition which is viscous by means of a self thickening system, and which is nevertheless easy to rinse away.
In response we have found that such a composition could be formulated by using an amine oxide, an amine or mixtures thereof, in combination with a secondary or primary monobranched alkyl sulfate or sulfonate in a mildly acidic system further comprising a hydrotrope and citric acid. An additional benefit derived from said compositions is that they are low foaming, both in the sense of the amount of foam initially generated during use, as well as in terms of foam stability. This benefit adds to the ease of rinsing benefit already obtained with the "mechanistic" benefit derived from the viscosity profile of the composition.